Integrated Aerial Photogrammetry Surveys

ABSTRACT

Novel tools and techniques for generating survey data about a survey site. Aerial photography of at least part of the survey site can be analyzed using photogrammetric techniques. In some cases, an unmanned aerial system can be used to collect site imagery. The use of a UAS can reduce the fiscal and chronological cost of a survey, compared to the use of other types aerial imagery and/or conventional terrestrial surveying techniques used alone.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/685,375, filed Nov. 26, 2012 by Kenneth R. Joyce et al. and titled,“Integrated Aerial Photogrammetry Surveys” (attorney docket no.0420.15), which is incorporated herein by reference in its entirety.

COPYRIGHT STATEMENT

A portion of the disclosure of this patent document contains materialthat is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure as it appears in the Patent and TrademarkOffice patent file or records, but otherwise reserves all copyrightrights whatsoever.

FIELD

The present disclosure relates, in general, to aerial photography andmore particularly, to novel solutions employing photogrammetric analysisof aerial photography.

BACKGROUND

Land surveys are an important part of the planning and constructionprocesses. Conventionally, preparing a land survey required extensiveuse of terrestrial survey instruments to obtain position measurements ofvarious features within the survey site. The expense of the equipmentinvolved, along with the required time commitment and labor-intensivenature of the measurements, necessarily requires considerable investmentin time and money prior to beginning any development activities.

On the other hand, aerial photography of a subject area can provide arelatively efficient way to quickly gain a rough understanding of thetopology of an area. Such photography, however, generally is performedusing aircraft and/or satellites, which necessarily entail significantcosts and administrative inconvenience. Moreover, aerial photographs,which necessarily are taken from altitudes ranging from several thousandfeet to several miles, cannot provide imagery with sufficient resolutionto allow analysis with the precision required for a land survey.

Accordingly, there is a need for more efficient techniques to generatedata necessary for land surveys.

BRIEF SUMMARY

A set of embodiments provides novel solutions for generating survey dataabout a survey site. In an aspect, some embodiments employ aerialphotography of at least part of the survey site, and in another aspect,some embodiments analyze the aerial photography using photogrammetrictechniques. Certain embodiments employ an unmanned aerial system (“UAS”)to collect site imagery. The use of a UAS can reduce the cost of asurvey, compared to the use of other aerial imagery (e.g., conventionalaerophotography and/or satellite imagery), which can require interactionwith regulatory authorities, leasing of expensive equipment, and/orsignificant advanced planning.

Further, some embodiments can provide accuracy and/or precisioncomparable to a conventional terrestrial survey at a lower cost, due toa need for fewer (or no) measurements taken using terrestrial surveyequipment. Instead, such embodiments can employ aerial photography tocapture site data relatively quickly. Unlike conventional aerialphotographs, however, the images captured by certain embodiments canhave sufficient resolution to allow photogrammetric analysis to generaterelatively precise and/or accurate position data about features ofinterest on the survey site. For example, in some embodiments, the UAScan capture site imagery from a height of less than 800 feet, whichwould be infeasible for conventional aerophotography.

In some cases, the data set generated from one or more aerialphotographs can be integrated with a data set generated from anotherdata source, such as a terrestrial survey instrument. Using thistechnique, aerial data can be supplemented with terrestrial survey datato orient the aerial data and/or to provide survey data in areas forwhich aerial data is unavailable or infeasible to collect, such as areasobscured from overhead visibility (e.g., areas under bridges or otherstructures, areas with heavy tree coverage, etc.).

The tools provided by various embodiments include, without limitation,methods, systems, and/or software products. Merely by way of example, amethod might comprise one or more procedures, any or all of which areexecuted by a computer system. Correspondingly, an embodiment mightprovide a computer system configured with instructions to perform one ormore procedures in accordance with methods provided by various otherembodiments. Similarly, a computer program might comprise a set ofinstructions that are executable by a computer system (and/or aprocessor therein) to perform such operations. In many cases, suchsoftware programs are encoded on physical, tangible and/ornon-transitory computer readable media (such as, to name but a fewexamples, optical media, magnetic media, and/or the like).

Merely by way of example, a method in accordance with one set ofembodiments might comprise operating an unmanned aerial system and/orcollecting, with the unmanned aerial system, imagery of a subject area.In some cases, the method can comprise producing, e.g., at a computer,feature data. In some cases, this feature data might be produced byanalyzing the imagery photogrammetrically. In further embodiments, themethod can include generating, (e.g., at the computer), a land surveybased at least in part on the feature data.

A method in accordance with another set of embodiments might compriseoperating an unmanned aerial system. The method might further includecollecting, with the unmanned aerial system, aerial imagery of a subjectarea. In some cases, the unmanned aerial system might transmit theimagery (e.g., via a wired or wireless link, in flight or post-flight),and the method might further comprise receiving, at a computer, theaerial imagery collected by the unmanned aerial system. In a typicalembodiment, the method can include producing, at the computer, a firstfeature data set by analyzing the aerial imagery photogrammetrically.

The method can also include combining the first feature data set with asecond feature data set to produce a combined feature data set. Thisoperation can also be performed by a computer programmed with softwareprovided by various embodiments. The second feature data set mightinclude any of a variety of different types of data, which can becollected from a variety of different data sources. Merely by way ofexample, in one embodiment, the second feature data set might comprisedata collected by one or more terrestrial survey instruments. On suchinstrument might be a panoramic imagery system, which can be used tocollect panoramic imagery (e.g., of at least a portion of the subjectarea), and the second feature data set might be generated by analyzingthe panoramic imagery photogrammetrically. In another aspect, the secondfeature data set might comprise feature data about a portion of thesubject area that is obscured from the unmanned aerial system and/orun-captured in the aerial imagery.

Different techniques can be used to combine multiple, different datasets. Merely by way of example, in one embodiment, an aerial featuredata set can be combined and/or integrated with a terrestrial surveyfeature data set by identifying one or more tie points in theterrestrial survey feature data set; in an aspect, each of the one ormore tie points might have a known location on a reference coordinatesystem. Next, a location can be identified, in the aerial imagery, ofeach of the one or more tie points. Each such location of one of the tiepoints in the aerial imagery can be correlated with a correspondingknown location on the reference coordinate system. Based on thecoordinated location of each of the one or more tie points, the aerialimagery can be oriented.

In another aspect, producing the first feature data set might comprisegenerating a first point cloud from the aerial imagery, and/or producingthe second feature data set might comprise generating a second pointcloud, e.g., from data collected by one or more terrestrial surveyinstruments. In this case, the combined data set comprises an integratedpoint cloud generated from the first point cloud and the second pointcloud.

The feature data set from the aerial imagery and/or a combined data setcan be used for a variety of purposes. Merely by way of example, in oneembodiment, the method can include generating, at the computer, a landsurvey of at least a portion of the subject areas, based at least inpart on the combined feature data set. In another embodiment, the methodcan comprise generating a terrain map from the land survey.

In other cases, the method might comprise presenting the imagery to auser. For example, in some cases, the method might comprise generatingan aerial ortho-image mosaic from the aerial imagery and correlating oneor more panoramic images with the aerial ortho-image mosaic. Thesecorrelated images can be presented in different ways. For instance, insome cases, the method might comprise presenting, in a user interface,the aerial imagery using a plan view, receiving user input to zoom intoan area of focus on the plan view, and/or presenting, in the userinterface, one or more panoramic images as three dimensional panoramabubbles corresponding to the area of focus. Alternatively and/oradditionally, the method might comprise presenting, in a user interface,the aerial imagery and the panoramic imagery integrated in athree-dimensional perspective.

An apparatus in accordance with yet another set of embodiments mightcomprise a computer readable medium having encoded thereon a set ofinstructions executable by one or more computers to perform one or moreoperations, including without limitation one or more operations inaccordance with methods provided by other embodiments. Merely by way ofexample, one set of instructions might comprise instructions to receiveaerial imagery collected by an unmanned aerial system and/orinstructions to produce a first feature data set by analyzing the aerialimagery photogrammetrically. The set of instructions might furthercomprise instructions to combine the first feature data set with asecond feature data set to produce a combined feature data set; thesecond feature data set might comprise data collected by one or moreterrestrial survey instruments. The set of instructions might furthercomprise instructions to generate a land survey of at least a portion ofthe subject areas, based at least in part on the combined feature dataset.

A system in accordance with another set of embodiments might comprise acomputer comprising a processor and non-transitory computer readablemedium having encoded thereon a set of instructions executable by theprocessor to perform one or more operations. As noted above, the set ofinstructions might be executable to perform one or more operations inaccordance with the methods provided by other embodiments. In somecases, the system might further comprise an unmanned aerial systemcomprising an imaging system configured to capture aerial imagery of asubject area. The imaging system, in one aspect, might feature aplurality of imaging devices configured to capture digital stereoimagery of the subject area.

In another embodiment, the system might comprise a terrestrial surveyinstrument configured to collect the data to produce a second featuredata set. Such terrestrial survey instruments can include, but are notlimited to, a total station, a camera (e.g., a panoramic camera) and/ora set of cameras, a laser scanner, an electronic distance measurementsystem (which might comprise a laser), a global navigation satellitesystem receiver, and/or the like.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of particularembodiments may be realized by reference to the remaining portions ofthe specification and the drawings, in which like reference numerals areused to refer to similar components. In some instances, a sub-label isassociated with a reference numeral to denote one of multiple similarcomponents. When reference is made to a reference numeral withoutspecification to an existing sub-label, it is intended to refer to allsuch multiple similar components.

FIG. 1 is a block diagram illustrating a system for performing aerialphotogrammetry in accordance with various embodiments.

FIGS. 2, 2A, and 2B are a process flow diagram illustrating a method ofaerial photogrammetry in accordance with various embodiments.

FIGS. 3 and 3A are a process flow diagram illustrating a method ofintegrating feature data sets, in accordance with various embodiments.

FIG. 4 is a generalized schematic diagram illustrating a computersystem, in accordance with various embodiments.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

While various aspects and features of certain embodiments have beensummarized above, the following detailed description illustrates a fewexemplary embodiments in further detail to enable one of skill in theart to practice such embodiments. The described examples are providedfor illustrative purposes and are not intended to limit the scope of theinvention.

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the described embodiments. It will be apparent to oneskilled in the art, however, that other embodiments of the present maybe practiced without some of these specific details. In other instances,certain structures and devices are shown in block diagram form. Severalembodiments are described herein, and while various features areascribed to different embodiments, it should be appreciated that thefeatures described with respect to one embodiment may be incorporatedwith other embodiments as well. By the same token, however, no singlefeature or features of any described embodiment should be consideredessential to every embodiment of the invention, as other embodiments ofthe invention may omit such features.

Unless otherwise indicated, all numbers used herein to expressquantities, dimensions, and so forth used should be understood as beingmodified in all instances by the term “about.” In this application, theuse of the singular includes the plural unless specifically statedotherwise, and use of the terms “and” and “or” means “and/or” unlessotherwise indicated. Moreover, the use of the term “including,” as wellas other forms, such as “includes” and “included,” should be considerednon-exclusive. Also, terms such as “element” or “component” encompassboth elements and components comprising one unit and elements andcomponents that comprise more than one unit, unless specifically statedotherwise.

Some embodiments include systems, methods, and/or software that cancapture, and/or photogrammetrically analyze, aerial imagery captured bya UAS. In some cases, these tools can generate, from such imagery,survey data about a survey site. The use of a UAS can provide severaladvantages: it can provide survey-quality data at a fraction of the timeand expense required for a survey produced from terrestrial surveyinstruments alone. For instance, a typical survey area for a UAS surveymight be approximately 2 km², which would require substantial time andexpense to survey with terrestrial instruments alone. For any site aboveapproximately 10 acres (and even sites smaller than that), however, theuse of a UAS can provide substantial enhancement in performance, andcorresponding reductions in cost, when compared with conventionalterrestrial surveying techniques

Further, a UAS can provide much higher quality imagery than conventionalaerophotography or satellite imagery, due to the vastly reduced altitudeof the UAS (as compared to an airplane or satellite). For example, a UAScan capture imagery at a height of between 100 and 800 feet above groundlevel (“AGL”), or more particularly, in some cases, a height of between300 and 600 feet AGL, altitudes that are infeasible or impossible for aconventional airplane or satellite to maintain with any degree ofsafety. As a result, while a conventional ground sampling distance(pixel size) for a conventional fixed wing platform is approximately 0.5m, a UAS provided by typical embodiments might provide a ground samplingdistance of approximate 2.0 cm.

Thus, unlike conventional aerial photographs, UAS imagery can providesufficient resolution to allow photogrammetric analysis to generaterelatively precise and/or accurate position data about features ofinterest on the survey site. Hence, such embodiments can provideaccuracy and/or precision comparable to a conventional terrestrialsurvey at a lower cost, due to a need for fewer (or no) measurementstaken using terrestrial survey equipment.

Further, the use of a UAS can avoid much of the cost and restrictionsimposed by more conventional aerophotography. In general, a low-levelflight by a UAS over a discrete survey site does not require filing of aformal flight plan, scheduling of aerial assets, or any of the myriadinconveniences associated with conventional aerophotography. Instead, asurvey team can launch the UAS ad hoc, at the survey site, and quicklygather sufficient imagery to allow a survey to be produced.

In some cases, the data set generated from one or more aerialphotographs can be integrated with a data set generated from one or moreother data sources, such as a terrestrial survey instruments. Using thistechnique, aerial data can be supplemented with terrestrial survey datato orient the aerial data and/or to provide survey data in areas forwhich aerial data is unavailable or infeasible to collect, such as areasobscured from overhead visibility (e.g., areas under bridges or otherstructures, areas with heavy tree coverage, etc.).

Further, the integration of terrestrial survey techniques with aerialsurvey techniques can provide numerous advantages over the use of eithertechnique exclusively. Merely by way of example, by integratinghistorical terrestrial survey data, an operator can expedite theplanning of aerial flight plans by informing the capture area of theaerial survey, for example, by providing known feature data, boundariesof the survey site, ground control target positioning, and/or the like.

In accordance with some embodiments, ground control points can beprocessed by the software as native data (e.g., in the same environmentas the aerial and/or terrestrial image processing), eliminating the needfor inconvenient and error-prone data import operations. Similarly,airborne GNSS data (e.g., data captured by an GNSS real time kinematics(“RTK”) receiver on the UAS) can be processed in the same environment,again, without the need for import operations and/or can be enhanced bydata received from terrestrial GNSS receivers. In this environment,terrestrial and aerial images (and/or other terrestrial survey data) canbe combined to measure individual features in the captured images), andin some cases, terrestrial and aerial images can be combinedphoto-realistic “virtual tours” of a project site.

Much of this functionality is enabled by the ability of the officesoftware provided by certain embodiments (and the methods performed bythat software and/or compute systems programmed with the software) totreat a UAS as a “flying total station.” In other words, the softwarehas the novel ability to treat airborne imagery and data in the samefashion as imagery and data captured terrestrially. Using thisfunctionality, imagery and data captured from a UAS or other airborneplatform can be integrated into any surveying workflow supported by theoffice software with respect to terrestrial measurements.

Turning to the figures, FIG. 1 illustrates a system 100 that can be usedto capture aerial imagery and/or to produce survey data therefrom, inaccordance with one set of embodiments. The system 100 comprises a UAS105. Some example of UAS that can be used with various embodiments aredescribed in International Publication No. WO 2011/131382, filed byGatewing N V and published Oct. 27, 2011, which is incorporated hereinby reference. An exemplary embodiment can employ a UAS such as theX100™, commercially available from Gatewing N V, although differentembodiments can employ any aerial platform that provides sufficientimage resolution to support the photogrammetry techniques describedherein.

In an aspect of some embodiments, the UAS 100 comprises an imagingsystem 110, which can be configured to capture aerial imagery of asubject area (e.g., a survey site and/or a portion thereof). A varietyof different imaging systems can be used in accordance with differentembodiments. Merely by way of example, the Gatewing X100™ features animaging system that provides sufficient performance. In someembodiments, the imaging system comprises a digital stereo imagingsystem (which might comprise a plurality of cameras or other imagecapture devices) that is configured to capture digital stereo imagery ofa subject area. An aerial system with multiple image sensors can becapable of mapping more terrain and generating more overlap betweenpasses with fewer flight lines. This can reduce the time to captureimagery and/or expand the coverage capability of the UAS.

As illustrated, the system 100 includes a control system 115, whichcommunicates with the UAS 105 to provide flight control information tothe UAS 105 and/or to receive data from the UAS 105. Such communicationsgenerally will be wireless radio-frequency (“RF”) communications,although wired communications are possible as well. In an exemplaryembodiment, the control system 115 can use ultra high frequency (“UHF”)communications to communicate with the UAS 105; in other embodiments, avariety of technologies, including cellular, wireless wide area network(“WWAN”) and the like can provide communications between the controlsystem 115 and the UAS 105. In an aspect, then, the control system 115can include (and/or can be in communication with) appropriatecommunication hardware to communicate with the UAS 105, such as awireless radio, etc. Correspondingly, the UAS 105 can include similarcommunication hardware for communicating with the control system 115.

The UAS 105 generally will also include a processing system (notillustrated by FIG. 1), which can receive commands from the controlsystem 115 and/or can control operation of the UAS 105 (such as movementof control surfaces, thrust and/or prop speed, etc.) and/or the imagingsystem 110. In some cases, the UAS 105 might transmit real-time imagerycaptured by the imaging system 110 to the control system 115, fordisplay to an operator, who can control operation of the US based on thereceived imagery. In some cases, this imagery might be stored by thecontrol system 115 for further photogrammetric analysis (e.g., asdescribed in further detail below).

Alternatively and/or additionally, the UAS 105 might include a storagemedium (not illustrated on FIG. 1), such as flash memory (which can bepermanently installed and/or removable, such as a USB drive), a diskdrive, etc., which can be used to store operational commands, capturedimagery, etc. In some cases, the UAS 105 might capture imagery at arelatively high resolution and transmit imagery to the control system115 at a relatively low resolution (e.g., due to bandwidth limitations).In such cases, the UAS 105 might store the high-resolution imagery onthe storage medium for download by the control system 115 (and/oranother device) post-flight, when higher download bandwidth (and/or moredownload time) is available.

In some embodiments, the system 100 might include an office computersystem 120, which is programmed with an office software package that canbe used to receive aerial and/or terrestrial images and/or data, performthe survey workflows, photogrammetric analysis, data set integration,and/or survey generation functions described in further detail below. Insome cases, the office computer system 120 might incorporate thefunctions of the control system 115 and a single computer system. Inother cases, the office computer system 120 may be in communication withthe control system 115 (e.g., using any of a variety of well-knownnetworking techniques). Hence, the office system 120 might be proximatethe control system 115 (e.g., at the survey site) and/or might be remotefrom the control system 115 (e.g., at an office location of the operatoror another user). In other cases, the office computer system might beindependent of the UAS 105 and/or the control system 115 and mightmerely receive data from those components (and/or others) using anyappropriate data transfer technique.

As illustrated by FIG. 1, the system 100 might include one or moreterrestrial survey instruments 125, which can collect feature data,e.g., in conventional fashion. This feature data can be combined withfeature data obtained from the aerial imagery, for example as describedin further detail below. In particular cases, a terrestrial surveyinstrument 125 might capture panoramic imagery, which can be integratedwith aerial imagery captured by the UAS 105, in accordance withembodiments discussed below. Terrestrial survey instruments 125 caninclude a variety of different instruments, including without limitationthose known to skilled artisans in the surveying field. Such instrumentscan include, without limitation, total stations 125 a (such as thoseavailable from Trimble Navigation Ltd.), global navigation satellitesystem (“GNSS”) receivers 125 b, laser scanners 125 c(includingthree-dimensional laser scanners, electronic distance measurement(“EDM”) systems that employ lasers to measure distances, etc.),panoramic cameras 125 d and/or any other instruments that can be used tocollect feature data about the subject area. Such feature data caninclude, but is not limited to, position data about tie points,reference points, and/or features of interest in the subject area,azimuth data, and/or the like.

Operation of the system 100 in accordance with various embodiments isdescribed in further detail below with regard to the methods of FIGS. 2and 3, but as a general matter, the system operates to collect aerialimagery with the UAS 105 and/or terrestrial survey data and/or panoramicimages with one or more terrestrial survey instruments 125 and toproduce correlated imagery, land surveys and/or other feature data fromone or more of these data sets. It should be noted that, while thesystem 100 might collect the aerial imagery/data and/or terrestrialsurvey instrument imagery/or data directly, in other aspects, componentsof the system (such as the office computer system 120) can functionusing data collected with other means (such as third-party data, etc.),so long as that data has sufficient accuracy and/or precision to provideusable output.

FIGS. 2 and 3 illustrate various methods that can be used to produce aland survey and/or other usable information from aerial imagery. Whilethe methods of FIGS. 2 and 3 are illustrated, for ease of description,as different methods, it should be appreciated that the varioustechniques and procedures of these methods can be combined in anysuitable fashion, and that, in some embodiments, the methods depicted byFIGS. 2 and 3 can be considered interoperable and/or as portions of asingle method. Similarly, while the techniques and procedures aredepicted and/or described in a certain order for purposes ofillustration, it should be appreciated that certain procedures may bereordered and/or omitted within the scope of various embodiments.Moreover, while the methods illustrated by FIGS. 2 and 3 can beimplemented by (and, in some cases, are described below with respect to)the system 100 of FIG. 1 (or components thereof), these methods may alsobe implemented using any suitable hardware implementation. Similarly,while the system 100 of FIG. 1 (and/or components thereof) can operateaccording to the methods illustrated by FIGS. 2 and 3 (e.g., byexecuting instructions embodied on a computer readable medium), thesystem 100 can also operate according to other modes of operation and/orperform other suitable procedures.

FIG. 2, for example, illustrates a method 200 of performing aerialphotogrammetry in accordance with various embodiments. In theillustrated embodiment, the method 200 comprises providing a userinterface (block 205). The user interface can provide interactionbetween a user (e.g., an operation of a UAS, a data analyst in asurveyor's office, etc.) and a computer system (e.g., a UAS controlsystem, an office computer system, an integrated office/control system,or any other type of computer system). For example, the user interfacecan be used to output information for a user, e.g., by displaying theinformation on a display device, printing information with a printer,playing audio through a speaker, etc.; the user interface can alsofunction to receive input from a user, e.g., using standard inputdevices such as mice and other pointing devices, motion capture devices,touchpads and/or touchscreens, keyboards (e.g., numeric and/oralphabetic), microphones, etc.

The procedures undertaken to provide a user interface, therefore, canvary depending on the nature of the implementation; in some cases,providing a user interface can comprise displaying the user interface ona display device; in other cases, however, in which the user interfaceis displayed on a device remote from the computer system (such as on aclient computer, wireless device, etc.), providing the user interfacemight comprise formatting data for transmission to such a device and/ortransmitting, receiving and/or interpreting data that is used to createthe user interface on the remote device. Alternatively and/oradditionally, the user interface on a client computer (or any otherappropriate user device) might be a web interface, in which the userinterface is provided through one or more web pages that are served froma computer system (and/or a web server in communication with thecomputer system), and are received and displayed by a web browser on theclient computer (or other capable user device). The web pages candisplay output from the computer system and receive input from the user(e.g., by using Web-based forms, via hyperlinks, electronic buttons,etc.). A variety of techniques can be used to create these Web pagesand/or display/receive information, such as JavaScript, Javaapplications or applets, dynamic HTML and/or AJAX technologies, to namebut a few examples.

In many cases, providing a user interface will comprise providing one ormore display screens, each of which includes one or more user interfaceelements. As used herein, the term “user interface element” (alsodescribed as a “user interface mechanism” or a “user interface device”)means any text, image, or device that can be displayed on a displayscreen for providing information to a user and/or for receiving userinput. Some such elements are commonly referred to as “widgets,” and caninclude, without limitation, text, text boxes, text fields, tablesand/or grids, menus, toolbars, charts, hyperlinks, buttons, lists, comboboxes, checkboxes, radio buttons, and/or the like. While any illustratedexemplary display screens might employ specific user interface elementsappropriate for the type of information to be conveyed/received bycomputer system in accordance with the described embodiments, it shouldbe appreciated that the choice of user interface elements for aparticular purpose is typically implementation-dependent and/ordiscretionary. Hence, the illustrated user interface elements employedby any display screens described herein should be considered exemplaryin nature, and the reader should appreciate that other user interfaceelements could be substituted within the scope of various embodiments.

As noted above, in an aspect of certain embodiments, the user interfaceprovides interaction between a user and a computer system. Hence, whenthis document describes procedures for displaying (or otherwiseproviding) information to a user, or for receiving input from a user,the user interface may be the vehicle for the exchange of suchinput/output. Merely by way of example, in a set of embodiments, theuser interface can allow a user to provide input regarding control of aUAS and/or aerial imaging system, review feature data collected by thesystem, view imagery, and/or the like.

For instance, some embodiments might allow for manual control of a UAS;such control might be provided through the user interface of a controlsystem (and/or through a dedicated remote control device). In othercases, however, the operator might want the UAS to overfly a particularsurvey site systematically to ensure proper imaging coverage of thatsite. In such cases, at block 210, the method 200 might compriseplanning a flight path for the UAS. For example, a computer system, suchas a control system, might receive user input via a user interface. Thisuser input might define an area (e.g., by address locations, GNSScoordinates, etc.) of which aerial imagery is desired.

The computer system, then, can plan a flight path for the UAS. Differentembodiments might weigh different factors more or less heavily inplanning the flight path. Merely by way of example, in some cases, thesystem might attempt to ensure the most efficient flight path (e.g., theflight path with the least travel time that still ensures photographiccoverage of the entire subject area). In other cases, the system mightplan the flight path to ensure comprehensive coverage, even at theexpense of efficiency, for example by ensuring that each point in thesubject area is captured in at least three (or more) images, etc. Takinginto account these considerations, a computer system (e.g., an officecomputer system, a control system, etc.) can define a flight path forthe UAS that ensures that the UAS will capture the desired imagery ofthe subject area. In some cases, the flight path might be defined as apattern, such as a grid, which will ensure adequate photographiccoverage to allow photogrammetric analysis. The computer can take intoaccount factors such as the orientation, resolution, focal length,and/or field of view, of the imaging system to determine altitude,number of passes over the subject area, horizontal distance betweenpasses, and/or the like.

The defined flight path can include both location of the UAS at variouspoints along the path, as well as locations and/or times at whichimagery should be captured. In some cases, the UAS might capture videoimagery, e.g., at 30 frames per second or any other appropriate framerate, in which case image capture parameters might not need to beincluded in the flight path. In other cases, the UAS might capture stillimages, either at specified intervals, and/or on command, in which casesuch intervals can be defined as part of the flight path.

In an aspect of particular embodiments, existing terrestrial survey datacan be used to plan the flight path, in several ways. Merely by way ofexample, terrestrial survey data can be used to determine the mappingextents of the survey area, for example by reference to a knowncoordinate system. Terrestrial survey data (such as GNSS coordinates, toname one example) can be used to determine the boundaries of the surveyarea, which then can inform outside boundaries of the flight path of theUAS. Additionally and/or alternatively, terrestrial survey data can beused to plan the flight path itself, for example to generate a flightpath that will ensure that the captured aerial imagery will include allportions of the survey site for which no terrestrial survey data exists,and/or to generate a flight path that does not include aerial coverageof any areas adequately captured by terrestrial surveying (with imageryand/or other measurements) or of obscured areas. Terrestrial survey datacan also be used at the planning stage to ensure that the flight path ofthe UAS will not intersect with power lines, buildings, or otherobstacles, and/or to generate a flight path that captures sufficientknown reference points (and/or tie points captured by terrestrialimagery) to enable orientation of the aerial images (by reference to aknown coordinate system and/or with respect to other aerial and/orterrestrial imagery). From these examples, one skilled in the art canascertain that existing terrestrial survey data can be used for avariety of functions in planning a UAS flight path.

In different embodiments, a UAS can be controlled in a variety of ways(subject, of course, to constraints imposed by the hardware and/orsoftware of the UAS). Merely by way of example, as noted above, in somecases, the UAS might be controlled manually through inputs at a controlsystem and/or the like. In other cases, the UAS might be equipped withonboard navigation equipment, such as a GNSS receiver, which can providethe UAS with the ability to follow a preprogrammed flight path.

In yet other embodiments, the UAS might navigate pursuant to theplacement of one or more ground targets, which the UAS might senseoptically, through the reception of RF signals emitted by the groundtargets, and/or the like. In such cases, the method 200 may comprisedirecting placement of ground control targets corresponding to theflight path (block 215). For instance, as noted above, terrestrialsurvey data can be used to plan the flight path, and the ground controltargets can be used, in some cases, to define that flight path. Hence,terrestrial survey data can be of use when determining where to placeground control targets to define the planned flight path. Merely by wayof example, an office computer system, control system, and/or the likemight identify locations on the ground (e.g., by GNSS coordinates, byreference to local features, and/or the like) at which ground controltargets should be placed in order to correctly guide the UAS on thespecified flight path. Such identification might be graphical (e.g., bysuperimposing images of the ground control targets on an overheadphotograph of the site) and/or graphical (e.g., by displaying, printing,etc.) address information, GNSS coordinates, and/or the like thatidentify, to whatever precision necessary, the location(s) at whichground control targets should be placed.

The method 200 might further comprise operating the UAS (block 220).Depending on the nature of the UAS control scheme (as described above),operating the UAS might merely comprise communicating a flight path froma ground-based control system to the UAS (either pre-flight orin-flight) and launching the craft. In other cases, the UAS mightrespond to the ground control targets automatically, such that operatingthe UAS merely requires launching the craft. In yet other cases,operating the UAS might comprise manually providing control inputs,e.g., via a ground-based control system.

At block 225, the method comprises collecting aerial imagery of asubject area, such as a survey site. In some cases, such imagery iscollected with the imaging system of a UAS, as described above, forexample. Depending on the embodiment, the imagery might be capturedautomatically and/or on command (e.g., from a ground-based controlstation). The imagery might be still photographs, digital stereophotographs, video, and/or the like. For example, in some cases, byreference to FIG. 2A, collecting aerial imagery might comprisecollecting aerial imagery from an altitude of between 100 and 800 feetAGL (block 225 a) and/or more particularly, in some cases, from analtitude of between 300 and 600 feet AGL (block 225 b). Alternativelyand/or additionally, collecting aerial imagery might comprise capturingdigital stereo imagery with the UAS (block 225 c).

At block 230, the UAS provides the aerial imagery to another device fordisplay, analysis, and/or the like. This operation can be accomplishedin a variety of different ways. Merely by way of example, as describedabove, the UAS might include a wireless and/or wired communicationsystem, and providing the aerial imagery might comprise transmitting theaerial imagery, using the communication system (e.g., over a network)and/or via a direct connection, such as a USB connection, to the otherdevice, which might be a control system, office computer system, and/orthe like. Such transmission might be performed in-flight, post-flight,and/or in any other appropriate manner. Alternatively and/oradditionally, the UAS might include a storage medium for storing theaerial imagery, and/or the storage medium might be removable. Forexample, in some cases, the UAS might store the imagery on a removablememory device (such as a flash drive, and/or the like), and providingthe imagery to another device may comprise removing the removable memoryand inserting the removable memory device into the device that is toreceive the aerial imagery. Other techniques for providing the imageryto other devices can be employed as well.

In some cases, the method 200 comprises receiving the aerial imagery ata computer system, such as an office computer system (block 235). Merelyby way of example, as noted above, in accordance with particularembodiments, a UAS might capture and transmit aerial imagery over awired connection, a wireless connection, and/or through transfer ofstorage media. Receiving the imagery at a computer system, therefore,can comprise receiving the transmission and/or obtaining the imageryfrom inserted storage media. In other cases, the computer system mayreceive imagery from a variety of other sources, such as othercomputers, online databases, and/or the like, using any of a variety ofwell-known data transfer techniques.

At block 240, the method 200 might comprise producing a feature data setfrom the aerial imagery. As used herein, the term, “feature data,” meansany data that describes, with appropriate precision, features of asubject area. Such features can include terrain features, man-madestructures, and/or any other geographic/topographic characteristics ofthe subject area. Merely by way of example, features can be representedwithin the software as points, lines, and/or polygons; examples offeatures can include things such as a fire hydrant (which might berepresented by a point), the centerline of a road (which could berepresented as a line), and a building footprint (which could berepresented by a polygon). Features can have geometry (location, size,and shape) as well as other non-location attributes such as color, size,condition, owner, etc.). Accordingly, feature data can include imagerythat is oriented according to a local or global coordinate system, pointclouds, coordinate descriptions of features and subject area, and/or thelike. A “feature data set,” then, means any set of data that describesthe features of some or all of a subject area.

In a particular aspect of some embodiments, the feature data set can beproduced by analyzing the aerial imagery photogrammetrically. A varietyof photogrammetric techniques are described, for example, in provisionalU.S. Patent Application No. 61/710,486, filed Oct. 5, 2012 by Grasser etal. and entitled “Enhanced Position Measurement Systems and Methods,”U.S. patent application Ser. No. 13/332,648, filed Dec. 21, 2011 byGrasser et al. and entitled “Enhanced Position Measurement Systems andMethods,” U.S. patent application Ser. No. 13/167,733 filed Jun. 24,2011 by Wang et al. and entitled “Method and Apparatus for Image-BasedPositioning, U.S. patent application Ser. No. 12/559,322, filed Sep. 14,2009 by Janky et al. and entitled “Image-Based Georeferencing,” and U.S.patent application Ser. No. 12/350,871, filed Jan. 8, 2009 by Vogel etal. and entitled “Method and System for Measuring Angles Based on 360Degree Images,” (collectively, the Incorporated Applications), all ofwhich are incorporated herein by reference.

For instance, a network of images that have at least a portion ofoverlapping coverage (captured area) can be processed to correctrelative image positions and orientations. This can be done byautomatically or manually finding common points between two or moreimages (“tie points”), which might be, but need not necessarily be,known reference points, and performing a bundle adjustment on the imagesto orient the images relative to one another (e.g., relative position inspace and/or relative orientation in three or fewer axes). Optionally,the adjustment can include GNSS observations to a well-known location onthe aircraft and/or registered ground control points (e.g., knownreference points). By including either of these types of surveyobservations, the user can create a precise connection between thefeatures extracted from the aerial data set and a mapping referenceframe.

Such techniques (and/or any other suitable techniques) can be used toorient an aerial image photogrammetrically and/or to create a featuredata set (e.g., a data set comprising position/orientation fixes and/orother feature data, as described above, for various features captured inthe image). For instance, one might preposition optical targets (whichcan be used as ground control targets) at known reference locations inthe subject area and/or in response to instructions generated by theoffice computer system, as described above. Based on the locations ofthe optical targets (or other identifiable features with knownlocations) in the aerial image, the position and/or orientation of theimage capture device on the UAS (or other aerial system) can bedetermined, using “reverse photogrammetry” techniques (also known in theart as a space resection) disclosed in one or more of the IncorporatedApplications. From that position and orientation information, along withthe captured aerial imagery the position of any other identifiablefeature captured in the image can be inferred, using otherphotogrammetric techniques described in the Incorporated Applications.Using similar techniques, including those described in the IncorporatedApplications, multiple aerial images (e.g., successive frames incaptured video, different still images, etc.) can be oriented relativeto one another (based on the respective positions within each image ofcommon features), and a feature data set comprising feature data aboutthe entire subject area (or a desired portion thereof) can be generated.

As noted above, a benefit of some embodiments is the ability tointegrate data from a plurality of feature data sets, including withoutlimitation aerial imagery, terrestrial imagery, aerial and/or GNSSobservations, and/or other terrestrial survey observations. In someembodiments, a single software package can accept all of these types ofdata as native data for processing in a common environment without theneed for import operations, data and/or format translations, etc. Thislevel of integration can produce significant gains in efficiency as wellas enhanced accuracy in the integrated data, due to the reduction oferrors and/or imprecision related to data import and the like. Inaccordance with different embodiments, a variety of differentintegration techniques are possible, depending on the data captured andthe deliverables to be produced from the data (which can include,without limitation, ortho-photo mosaics, feature databases, terrainmaps, virtual tours, etc.).

For instance, in some embodiments, the data might include a feature dataset from one or more terrestrial survey instruments, such as thosedescribed above. Hence, at block 245, the method 200 can comprisecombining a first feature data set (e.g., a feature data set obtainedfrom aerial imagery) with a second feature data set (e.g., a featuredata set comprising data obtained from one or more terrestrial surveyinstruments). Many techniques may be suitable for combining feature datasets in this fashion, and the combination of feature data sets can servea variety of purposes.

Merely by way of example, in some cases, combining feature data sets cancomprise fixing the position of the UAS at the point of image capturethrough integration of GNSS data from a ground-based receiver with GNSSdata from a receiver on the UAS (e.g., using RTK techniques). Similarly,the orientation of the image capture device can be fixed usingphotogrammetric techniques by reference to known reference points (whichcan be part of a terrestrial feature data set) and/or by reference totie points in terrestrial images.

In other cases, an aerial survey feature data set can be combined with aterrestrial data set by integrating with the aerial data set featuredata from the terrestrial data set for areas that are obscured fromoverhead views or difficult to capture from overhead. In addition toareas with significant foliage cover or bridge overhangs, the use ofterrestrial imagery and/or data can be useful to supplement aerialimagery for features that are not amenable to overhead capture. Examplesinclude measurement of the base of a building (which can be obscured byeaves and/or the like), as well as measurement of stacked power lines,which can be difficult to discern from overhead imagery).

Taking the case of stacked power lines, for example, a UAS might captureaerial imagery by flying a flight path longitudinally over the powerlines for some distance. A terrestrial surveyor might also captureterrestrial panoramic imagery along the route of the power lines with atotal station or similar device, and this terrestrial imagery can beoriented based on terrestrial measurements taken while capturing theterrestrial images (or at another time), e.g., using techniquesdescribed in the Incorporated Applications. With regard to position,these fixes are reasonably precise, but the angular orientation isgenerally not terribly precise (and might be, for instance, limited tothe level of precision of a compass on the total station). Conventionalback sighting techniques (or others) can be used to orient these imagesmore precisely, but these techniques can be time consuming and/or canrequire significant additional terrestrial measurements. On the otherhand, the rough orientation provided by the compass on the total stationcan be sufficient to provide starting point for a bundle adjustmentusing the terrestrial panoramic images and the aerial images. Thus, theaerial imagery, although perhaps not terribly useful to measure thepower lines themselves, can be used to orient the terrestrial images,which then can be used to measure the power lines. This functionality isenabled, in various embodiments, by the ability of the processingsoftware to treat the aerial imagery and the terrestrial imagery assimilar data in a common environment, as described above.

To illustrate some more examples of integration of feature data sets,FIG. 3 depicts a method 300 of combining feature data sets. In somecases, for instance, the terrestrial survey instrument(s) might includecameras or other imaging systems capable of capturing panoramic imagery(e.g., from ground level) of the subject area. Examples of suchterrestrial survey instruments are described in the IncorporatedApplications. The method 300, then, can include collecting panoramicimagery with such a panoramic imagery system (block 305). This panoramicimagery can be analyzed photogrammetrically (block 310), for example asdescribed above with regard to the aerial imagery. This analysis canproduce a second feature data set from the data (in this case, panoramicimagery) collected by the terrestrial survey instrument.

In other cases, the terrestrial survey instrument(s) might producefeature data that does not require photogrammetric analysis. Forexample, a total station, GNSS device, laser device (such as athree-dimensional laser scanner, EDM system, etc.) might provideposition data for various features in the subject area, and a featuredata set could be generated from this ground-based survey data. In fact,one technique for combining feature data sets is to use ground-basedsurvey data to infer positions of the reference points in the aerialimagery, which then can provide those inferred positions as knownreference positions to allow for photogrammetric analysis of thoseimages, as described above.

For instance, the method 300 might comprise identifying, in a featuredata set generated from data collected by a terrestrial surveyinstrument, one or more tie points (block 315). These tie points mightbe identified by description and/or by position. Merely by way ofexample, an optical target might be identified as “Target 1” andassigned a position defined by latitude/longitude/elevation values. Aparticular feature might be identified as “Building—NW corner” andassigned a position. These positions might be determined by terrestrialsurvey techniques (e.g., azimuth/distance from a known measurementlocation, GNSS fix, etc.) by photogrammetric analysis of panoramicimagery, and/or the like. In a particular aspect, each of these tiepoints might be assigned a position in a reference coordinate system(which might be, as noted above, a global latitude/longitude/elevationcoordinate system or any other appropriate local or global coordinatesystem).

The method 300 might further comprise, identifying, in one or moreaerial images, locations of each of the identified tie points. Thelocations in the images might be expressed, for example, as (X,Y) pixelcoordinates from an origin in the image, which might be the top-leftcorner of the image, the center of the image, etc. These locations(e.g., pixel coordinates) can then be correlated to the correspondingknown position of the tie points in the reference coordinate system(block 320), which associates a particular pixel coordinate in theaerial image with a known position in the reference coordinate system.Using, e.g., the photogrammetric techniques disclosed in theIncorporated Applications, then, the aerial image can be oriented basedon the correlated pixel coordinates of the tie points (block 325). Theorientation of the aerial image can establish the position of the imagecapture device that too the image as well as the three-axis orientationof the field of view that image capture device. Once the aerial imagehas been oriented, as noted above, the position of any feature in theimage can be determined photogrammetrically.

Two or more feature data sets can be combined in other ways as well,however. Merely by way of example, one feature data set might compriseoriented aerial imagery and another feature data set might compriseoriented panoramic imagery (taken from ground level), and based on theorientation of each of the aerial and panoramic imagery, respectively,the feature data sets could be combined to correlate the orientation ofeach of images (which can provide enhanced functionality for presentingthe imagery to a user, as described in further detail below, forexample). For example, with reference to FIG. 3A, the aerial imagerycould be used to generate an aerial ortho-mosaic image (block 330)(e.g., from multiple aerial images that have been orientedphotogrammetrically with respect to one another) and then correlate oneor more panoramic images with the aerial ortho-mosaic image (block 335)(e.g., based on respective pixel-coordinates of features captured ineach of the images and/or based on the inferred orientations of theimage capture devices that captured each of the respective images).Further, once the aerial and terrestrial images are positioned and/ororiented, a user can measure individual features using the combinationof aerial and terrestrial imagery. For instance, the user can preciselymeasure the 3D locations of points by intersecting light rays capturedby (1) a terrestrial panoramic system and (2) an aerial imaging system.For example, as noted above, complex objects such as multi-layer powerlines can be efficiently and precisely mapped with a combination ofaerial and terrestrial imaging.

As another example of combining multiple feature data sets, someembodiments might generate a point cloud, which can serve as a firstfeature data set, from the photogrammetric analysis of an aerial image(or an aerial mosaic). The point cloud might describe, as a plurality ofpoints, each feature of a subject area. Similarly, the system mightgenerate a point cloud from other data (e.g. panoramic photos,measurements from terrestrial survey instruments, etc.), which can serveas a second data set. These two point clouds can be integrated (as eachpoint in each cloud is defined as a point in three-dimensional space),and the integrated point cloud can serve as a combined data set. Thistechnique might be useful, for example, to allow terrestrial surveymeasurements to orient an aerial image (by correlating the points ineach cloud for a common feature, for example) and/or to fill “gaps” inaerial coverage with terrestrial survey measurements. Moreover, itshould be noted that many of these techniques can be combined; forexample, the generation of an integrated point cloud can be used toorient an aerial image (as noted above), and/or terrestrial surveymeasurements can be used to orient both a panoramic image and an aerialimage, etc.

Returning to FIG. 2, the method 200 can include, at block 250,generating a land survey from a feature data set (which might includefeature data generated from aerial data and/or might comprise a combineddata set include feature data obtained, e.g., from terrestrial surveyinstruments). As noted above, aerial imagery (and/or other feature data)might be captured about a particular subject area, and the land surveymight cover at least a portion of that subject area. As used herein, a“land survey” means a formatted representation of material features of asubject area, which can include (without limitation) the terrain,manmade objects, and land ownership information, that has sufficientaccuracy and precision to allow the representation to serve as a guidefor desired activities, which can include, without limitation, land-useplanning, scientific studies, construction, and/or the like. As oneskilled in the art will appreciate, conventional survey techniquesemploy the position measurement of all material features of a surveysite and the generation of a survey therefrom. Using aerial photographyand the photogrammetric techniques described above and in theIncorporated Applications, various embodiments can fix positions ofmaterial features in the subject area with sufficient precision to allowgeneration of a land survey—in other words, the feature data setgenerated from the aerial imagery can substitute for some or all of themeasurements that conventionally would be performed by terrestrialsurvey instruments. (Of course, as necessary, this feature data set canbe combined with additional feature data sets obtained by terrestrialsurveying methods, as noted above, to provide feature data about aportion of the subject area obscured from the UAS and/or un-captured inthe aerial imagery, to provide orientation of the imagery, etc. Even inthis case, however, the use of aerial imagery can dramatically reducethe number of terrestrial survey measurements required for propercoverage of the subject area.)

Certain embodiments might provide additional functionality. Merely byway of example, in some cases, the method 200 might include generating aterrain map from the land survey (block 255). A terrain map might showfeatures of interest and any other characteristics of the survey area,such as topographical lines, that might be desired and can be inferredfrom photogrammetric analysis of the aerial photography (and/orsupplemented as necessary by terrestrial survey measurements). Asanother example, integrated aerial survey data can be used foragricultural studies and planning. For instance, a farmer could use theimagery to count trees in an orchard, determine which trees are growingwell/poorly, and adjust planting, watering, fertilizer, pesticidesand/or other variables accordingly. Similarly, an airport could use thecombination of aerial and terrestrial photography to study glide pathsinto precision approaches and provide analysis for building permittingand tree-cutting. In an open-pit mine, for instance, the integratedapplication might be used daily to study the volume of materials removedand/or safety of wall slopes. From these examples, one skilled in theart can appreciate that integrated aerial surveys provided by variousembodiments can be useful in many different fields and applications.

Returning to FIG. 2, the method 200 might comprise presenting, at block260, the aerial imagery and/or ground-level panoramic imagery to a user(e.g., via the user interface of an office computer system, etc.). Forinstance, as described above, the system might generate an aerialortho-image mosaic from the aerial imagery and/or correlate one or morepanoramic images with the aerial ortho-image mosaic (or other aerialimagery). The method 200, then, might include presenting, e.g., in theuser interface, the collected aerial imagery using a plan view (block260) and/or receiving user input to zoom into an area of focus on theplan view (block 265). The method 200 might further include presenting,in the user interface, one or more panoramic images corresponding to thearea of focus (block 270). These panoramic images could correspond tothe area of focus identified by the user input. A variety of differentpresentation techniques might be used to present this imagery.

Merely by way of example, by reference to FIG. 2B, the panoramic imagerymight be presented as three dimensional panorama bubbles correspondingto the area of focus (block 270 a). In such an implementation, the usermight be presented with an aerial (overhead) view of the subject area,and when the user selects (e.g., clicks on) a particular portion of thatimage, the system might display panoramic images captured from theground position that corresponds to that portion of the aerial image (oras close to that position as possible). Alternatively and/oradditionally, the aerial imagery and the panoramic imagery might bepresented as integrated in a three-dimensional perspective (block 270b). As an example, the combined aerial and terrestrial imagery can beused to create an engineering-grade “virtual tour” of a location, inwhich views from a variety of angles (including, in some cases, acontinuous spectrum of angles) from over-head to human-perspective areavailable for visualization and measuring. This functionality is aresult of the realization that, at a certain level of abstraction, a UAScan perform as a flying total station that is working in an angles-onlymode; in this role, the UAS can collect many features/observations atonce. As such the same techniques that display and manipulatetraditional survey data (e.g. collected by a total station) can also beused with UAS-collected imagery and/or data (including withoutlimitation data derived from such imagery).

As an additional or alternative feature, the method 200 might comprisetracking historical features of the subject area (block 275). Forexample, the system might generate a plurality of land surveys atdifferent times over a period of days, weeks, months, or years, andhistorical features of the subject area might be tracked based on thisplurality of land surveys. These surveys (and/or, more particularly, theoverhead images associated with each survey) could be presented to theuser in the manner of time lapse photography, allowing the user to see,over time, how the subject area has developed. Because the images areassociated with land surveys, detailed feature data would be availablefor different points in time, and this feature data could be analyzed todetermine, for example, a degree of erosion of a shoreline, growth of amine tailings pile, and/or the like. Similarly, for construction sites,the locations of buried utilities or simply the location of constructionequipment can be re-created at a later date.

FIG. 4 provides a schematic illustration of one embodiment of a computersystem 400 that can perform the methods provided by various otherembodiments, as described herein, and/or can function as a ground-basedcontrol system for a UAS, an office computer system, an integratedoffice/control system, and/or an onboard computer/control system on theUAS itself, which could function to receive and store controlinformation, operate the imaging system, communicate images to aground-based system, and/or the like. It should be noted that FIG. 4 ismeant only to provide a generalized illustration of various components,of which one or more (or none) of each may be utilized as appropriate.FIG. 4, therefore, broadly illustrates how individual system elementsmay be implemented in a relatively separated or relatively moreintegrated manner.

The computer system 400 is shown comprising hardware elements that canbe electrically coupled via a bus 405 (or may otherwise be incommunication, as appropriate). The hardware elements may include one ormore processors 410, including without limitation one or moregeneral-purpose processors and/or one or more special-purpose processors(such as digital signal processing chips, graphics accelerationprocessors, and/or the like); one or more input devices 415, which caninclude without limitation a mouse, a keyboard and/or the like; and oneor more output devices 420, which can include without limitation adisplay device, a printer and/or the like.

The computer system 400 may further include (and/or be in communicationwith) one or more storage devices 425, which can comprise, withoutlimitation, local and/or network accessible storage, and/or can include,without limitation, a disk drive, a drive array, an optical storagedevice, solid-state storage device such as a random access memory(“RAM”) and/or a read-only memory (“ROM”), which can be programmable,flash-updateable and/or the like. Such storage devices may be configuredto implement any appropriate data stores, including without limitation,various file systems, database structures, and/or the like.

The computer system 400 might also include a communications subsystem430, which can include without limitation a modem, a network card(wireless or wired), an infra-red communication device, a wirelesscommunication device and/or chipset (such as a Bluetooth™ device, an802.11 device, a WiFi device, a WiMax device, a WWAN device, cellularcommunication facilities, etc.), and/or the like. The communicationssubsystem 430 may permit data to be exchanged with a network (such asthe network described below, to name one example), with other computersystems, and/or with any other devices described herein. In manyembodiments, the computer system 400 will further comprise a workingmemory 435, which can include a RAM or ROM device, as described above.

The computer system 400 also may comprise software elements, shown asbeing currently located within the working memory 435, including anoperating system 440, device drivers, executable libraries, and/or othercode, such as one or more application programs 445, which may comprisecomputer programs provided by various embodiments, and/or may bedesigned to implement methods, and/or configure systems, provided byother embodiments, as described herein. Merely by way of example, one ormore procedures described with respect to the method(s) discussed abovemight be implemented as code and/or instructions executable by acomputer (and/or a processor within a computer); in an aspect, then,such code and/or instructions can be used to configure and/or adapt ageneral purpose computer (or other device) to perform one or moreoperations in accordance with the described methods.

A set of these instructions and/or code might be encoded and/or storedon a non-transitory computer readable storage medium, such as thestorage device(s) 425 described above. In some cases, the storage mediummight be incorporated within a computer system, such as the system 400.In other embodiments, the storage medium might be separate from acomputer system (i.e., a removable medium, such as a compact disc,etc.), and/or provided in an installation package, such that the storagemedium can be used to program, configure and/or adapt a general purposecomputer with the instructions/code stored thereon. These instructionsmight take the form of executable code, which is executable by thecomputer system 400 and/or might take the form of source and/orinstallable code, which, upon compilation and/or installation on thecomputer system 400 (e.g., using any of a variety of generally availablecompilers, installation programs, compression/decompression utilities,etc.) then takes the form of executable code.

It will be apparent to those skilled in the art that substantialvariations may be made in accordance with specific requirements. Forexample, customized hardware (such as programmable logic controllers,field-programmable gate arrays, application-specific integratedcircuits, and/or the like) might also be used, and/or particularelements might be implemented in hardware, software (including portablesoftware, such as applets, etc.), or both. Further, connection to othercomputing devices such as network input/output devices may be employed.

As mentioned above, in one aspect, some embodiments may employ acomputer system (such as the computer system 400) to perform methods inaccordance with various embodiments of the invention. According to a setof embodiments, some or all of the procedures of such methods areperformed by the computer system 400 in response to processor 410executing one or more sequences of one or more instructions (which mightbe incorporated into the operating system 440 and/or other code, such asan application program 445) contained in the working memory 435. Suchinstructions may be read into the working memory 435 from anothercomputer readable medium, such as one or more of the storage device(s)425. Merely by way of example, execution of the sequences ofinstructions contained in the working memory 435 might cause theprocessor(s) 410 to perform one or more procedures of the methodsdescribed herein.

The terms “machine readable medium” and “computer readable medium,” asused herein, refer to any medium that participates in providing datathat causes a machine to operation in a specific fashion. In anembodiment implemented using the computer system 400, various computerreadable media might be involved in providing instructions/code toprocessor(s) 410 for execution and/or might be used to store and/orcarry such instructions/code (e.g., as signals). In manyimplementations, a computer readable medium is a non-transitory,physical and/or tangible storage medium. Such a medium may take manyforms, including but not limited to, non-volatile media, volatile media,and transmission media. Non-volatile media includes, for example,optical and/or magnetic disks, such as the storage device(s) 425.Volatile media includes, without limitation, dynamic memory, such as theworking memory 435. Transmission media includes, without limitation,coaxial cables, copper wire and fiber optics, including the wires thatcomprise the bus 405, as well as the various components of thecommunication subsystem 430 (and/or the media by which thecommunications subsystem 430 provides communication with other devices).Hence, transmission media can also take the form of waves (includingwithout limitation radio, acoustic and/or light waves, such as thosegenerated during radio-wave and infra-red data communications).

Common forms of physical and/or tangible computer readable mediainclude, for example, a floppy disk, a flexible disk, a hard disk,magnetic tape, or any other magnetic medium, a CD-ROM, any other opticalmedium, punch cards, paper tape, any other physical medium with patternsof holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chipor cartridge, a carrier wave as described hereinafter, or any othermedium from which a computer can read instructions and/or code.

Various forms of computer readable media may be involved in carrying oneor more sequences of one or more instructions to the processor(s) 410for execution. Merely by way of example, the instructions may initiallybe carried on a magnetic disk and/or optical disc of a remote computer.A remote computer might load the instructions into its dynamic memoryand send the instructions as signals over a transmission medium to bereceived and/or executed by the computer system 400. These signals,which might be in the form of electromagnetic signals, acoustic signals,optical signals and/or the like, are all examples of carrier waves onwhich instructions can be encoded, in accordance with variousembodiments of the invention.

The communications subsystem 430 (and/or components thereof) generallywill receive the signals, and the bus 405 then might carry the signals(and/or the data, instructions, etc. carried by the signals) to theworking memory 435, from which the processor(s) 405 retrieves andexecutes the instructions. The instructions received by the workingmemory 435 may optionally be stored on a storage device 425 eitherbefore or after execution by the processor(s) 410.

While certain features and aspects have been described with respect toexemplary embodiments, one skilled in the art will recognize thatnumerous modifications are possible. For example, the methods andprocesses described herein may be implemented using hardware components,software components, and/or any combination thereof. Further, whilevarious methods and processes described herein may be described withrespect to particular structural and/or functional components for easeof description, methods provided by various embodiments are not limitedto any particular structural and/or functional architecture but insteadcan be implemented on any suitable hardware, firmware and/or softwareconfiguration. Similarly, while certain functionality is ascribed tocertain system components, unless the context dictates otherwise, thisfunctionality can be distributed among various other system componentsin accordance with the several embodiments.

Moreover, while the procedures of the methods and processes describedherein are described in a particular order for ease of description,unless the context dictates otherwise, various procedures may bereordered, added, and/or omitted in accordance with various embodiments.Moreover, the procedures described with respect to one method or processmay be incorporated within other described methods or processes;likewise, system components described according to a particularstructural architecture and/or with respect to one system may beorganized in alternative structural architectures and/or incorporatedwithin other described systems. Hence, while various embodiments aredescribed with—or without—certain features for ease of description andto illustrate exemplary aspects of those embodiments, the variouscomponents and/or features described herein with respect to a particularembodiment can be substituted, added and/or subtracted from among otherdescribed embodiments, unless the context dictates otherwise.Consequently, although several exemplary embodiments are describedabove, it will be appreciated that the invention is intended to coverall modifications and equivalents within the scope of the followingclaims.

What is claimed is:
 1. A method, comprising: operating an unmannedaerial system; collecting, with the unmanned aerial system, imagery of asubject area; and producing, at a computer, a first feature data set byanalyzing the imagery photogrammetrically; and generating, at thecomputer, a land survey based at least in part on the first feature dataset.
 2. The method of claim 1, further comprising: collecting data withone or more terrestrial survey instruments; producing a second featuredata set from the data collected with the one or more terrestrial surveyinstruments; and combining the first feature data set with the secondfeature data set to produce a combined feature data set; whereingenerating a land survey of at least a portion of the subject areacomprises generating a land survey based at least in part on thecombined feature data set.
 3. The method of claim 2, wherein combiningthe first feature data set with the second feature data set comprises:identifying one or more tie points in the second feature data set, eachof the one or more tie points having a known position in a referencecoordinate system; identifying a pixel coordinate, in the aerialimagery, of each of the one or more tie points; and correlating eachpixel coordinate of one of the tie points in the aerial imagery with acorresponding known position on the reference coordinate system; andorienting the aerial imagery based on the correlated pixel coordinate ofeach of the one or more tie points.
 4. The method of claim 2, whereinthe one or more terrestrial survey instruments comprises a panoramicimagery system, and wherein the method further comprises: collectingpanoramic imagery with the panoramic imagery system; and generating thesecond feature data set by analyzing the panoramic imageryphotogrammetrically.
 5. The method of claim 4, further comprising:generating an aerial ortho-image mosaic from the aerial imagery; andcorrelating one or more panoramic images with the aerial ortho-imagemosaic.
 6. The method of claim 5, further comprising: presenting, in auser interface, the aerial imagery using a plan view; receiving userinput to zoom into an area of focus on the plan view; and presenting, inthe user interface, one or more panoramic images as three dimensionalpanorama bubbles corresponding to the area of focus.
 7. The method ofclaim 5, further comprising: presenting, in a user interface, the aerialimagery and the panoramic imagery integrated in a three-dimensionalperspective.
 8. The method of claim 2, wherein producing the firstfeature data set comprises generating a first point cloud from theaerial imagery, producing the second feature data set comprisesgenerating a second point cloud from the data collected by one or moreterrestrial survey instruments, and the combined data set comprises anintegrated point cloud generated from the first point cloud and thesecond point cloud.
 9. The method of claim 2, wherein the second featuredata set comprises feature data about a portion of the subject areaobscured from the unmanned aerial system and un-captured in the aerialimagery
 10. The method of claim 1, wherein collecting aerial imagerycomprises collecting aerial imagery from an altitude of between 100 feetand 800 feet above ground level.
 11. The method of claim 1, whereincollecting aerial imagery comprises collecting aerial imagery from analtitude of between 300 feet and 600 feet above ground level.
 12. Themethod of claim 1, wherein collecting aerial imagery comprises capturingdigital stereo imagery with the unmanned aerial system.
 13. The methodof claim 1, further comprising: planning, with a computer, a flight pathfor the unmanned aerial system; and directing, with the computer,placement of ground control targets corresponding to the flight path.14. The method of claim 1, further comprising: tracking historicalfeatures of the subject area, based on a plurality of land surveysgenerated at different times.
 15. The method of claim 1, furthercomprising: generating, with the computer, a terrain map from the landsurvey.
 16. The method of claim 1, wherein producing the first featuredata set comprises generating a point cloud from the aerial imagery. 17.A system, comprising: an unmanned aerial system comprising an imagingsystem configured to capture aerial imagery of a subject area; and acomputer comprising one or more processors and a non-transitory computerreadable medium having encoded thereon a set of instructions executableby the computer system to: receive the aerial imagery from the unmannedaerial system; produce a first feature data set by analyzing the aerialimagery photogrammetrically; and generate a land survey of at least aportion of the subject area, based at least in part on the first featuredata set.
 18. The system of claim 17, wherein the imaging systemcomprises a plurality of imaging devices configured to capture digitalstereo imagery of the subject area.
 19. The system of claim 17, furthercomprising: a terrestrial survey instrument configured to collect datato produce a second feature data set; wherein the set of instructions isfurther executable by the processor to combine the first feature dataset with the second feature data set to produce a combined feature dataset; and wherein the instructions executable to generate a land surveyof at least a portion of the subject area comprise instructionsexecutable to generate a land survey based at least in part on thecombined feature data set.
 20. The system of claim 19, wherein theterrestrial survey instrument comprises a total station.
 21. The systemof claim 19, wherein the terrestrial survey instrument comprises apanoramic camera.
 22. The system of claim 19, wherein the terrestrialsurvey instrument comprises a laser scanning system.
 23. The system ofclaim 19, wherein the terrestrial survey instrument comprises a globalnavigation satellite system (“GNSS”) receiver.
 24. An apparatus,comprising: a computer readable medium having encoded thereon a set ofinstructions executable by one or more computers to: receive the aerialimagery from the unmanned aerial system; produce a first feature dataset by analyzing the aerial imagery photogrammetrically; and generate aland survey of at least a portion of the subject area, based at least inpart on the first feature data set.
 25. A computer system, comprising:one or more processors; and a computer readable medium in communicationwith the one or more processors, the computer readable medium havingencoded thereon a set of instructions executable by the computer systemto: receive the aerial imagery from an unmanned aerial system; produce afirst feature data set by analyzing the aerial imageryphotogrammetrically; and generate a land survey of at least a portion ofthe subject area, based at least in part on the first feature data set.